It's not a game anymore... Microsoft introduces rankings to Visual Studio! http://www.geekwire.com/2012/coding-fun-microsofts-visual-studio-badges-leaderboard/
Very pretty leaderboard featuring the greats from the Australian open - it's based on Twitter and Facebook mentions. Check it out at http://www.australianopen.com/en_AU/fancentre/social/index.html
Developer centric leaderboard and gamified community. I like this because the barrier to entry for a participant is high. Being a developer takes time (obviously). This isn't about people's passing fancies. Here gamification is about real dedication. http://coderwall.com/leaderboard